Flexible respirator with inflatable frame

ABSTRACT

A respirator, i.e. a face mask provided with a filter for respiratory use, comprising a substantially ring-shaped inflatable frame consisting of tubular foil material supporting a flexible wall having a perforated central portion to which the filter is attached. The central portion of the wall is stretched in a substantially planar state by the inflated frame and the filter is designed as a flexible disc-shaped pad covering the perforated portion of the wall.

United States Patent Stranicky [4 Aug. 7, 1973 [54] FLEXIBLE RESPIRATOR WITH 2,047,216 7/1936 McKesson 128/195 INFLATABLE FRAME 3,276,445 10/1966 Langdon 1,070,986 8/1913 Richter 128/195 [76] Inventor: Fedor Stranicky, 29

Ankdammsgaten, 17143 Solna, Sweden [22] Filed: June 21, 1971 [21] Appl. No.: 154,914

[] Foreign Application Priority Data Sept. 8, 1970 Sweden 12197/ [52] 11.8. C1 128/146.6, 128/140 N, 128/146.7 [51'] Int. Cl A621) 23/00 {58] Field of Search 128/146, 146.2, 146.3, l28/146.6, 146.7, 147, 195, 205,198, 206, N

[56] References Cited UNITED STATES PATENTS 712,304 10/1902 Jacobs et al. 128/147 ll.-ll I -11 III III I/AII/IIYII" Primary Examiner-William E. Kamm Attorney-John G. Schwartz et a1.

[57] ABSTRACT A respirator, i.e. a face mask provided with a filter for respiratory use, comprising a substantially ring-shaped inflatable frame consisting of tubular foil material supporting a flexible wall having a perforated central portion to which the filter is attached. The central portion of the wall is stretched in a substantially planar state by the inflated frame and the filter is designed as a flexible disc-shaped pad covering the perforated portion of the wall.

3 Claims, 6'Drawing Figures PATEWEBAUB U873 39 gggg FLEXIBLE RESPIRATOR WITH INFLATABLE FRAME Air pollution from industrial plants, heating plants and cars consititute a considerable risk to the health of people. Fumes from burning coal, soot and ash are the most common pollutants containing solid particles, and among the gases the sulphur compounds are dominating. As a rule the atmosphere can absorb these pollutants, so that no harmful effects arise to people, but in case of unfavorable weather conditions, e.g. long-term mist or fog, the proportion of pollution rises to a harmful level. This occurred, for example, in London in 1952 and caused the death of about 4,000 persons due to so called smog. Moreover, the exhaust gases from cars contain among other compounds hydrocarbons, which under the influence of sunlight are converted into compounds harmful to people, and a connection between increased air pollution and increased lung cancer has been established. In many great cities, such as Tokyo and Los Angeles, a type of smog" injurious to health and caused for all by the combination of exhaust gases from cars and geographical conditions occurs increasingly often.

The present invention relates toa respirator, i.e. a face mask for respiratory use, comprising a filter for filtering the breathing air of pollutants, said respirator being provided with an inflatable tubular frame consisting of flexible material, which frame in inflatable state is substantially ring-shaped and supports a wall provided with openings for passing the air via the filter. The respirator is particularly suitable for use as a pro tection against air pollution of the above-mentioned kind but it is also suitable as a protective mask for industrial purposes and asa civil defense gas-mask.

Respirators heretofore available and comprising a filter for filtering the breathing air usually consist of a moulded rubber mask, carefully designed to conform to the contour of the human face and having a soft rubber air cushion, which assures a tight fit with least possible pressure on the face, and a relatively large filter box containing the filter material. Respirators of this type are expensive and complicated in manufacture, also they are bulky and have to be manufactured in different sizes in order to fit a wide variety of facial contours. It is also known to use simple temporary masks in the shape of a sheet of cloth fitted to cover the nose and mouth and attached by means of elastic bands. Face masks of this kind are cheap, can easily be carried in ones pocket and are easily applied, The filtering effect, however, is poor due to the fact that the edges of the mask do not sufficiently seal against the face of the wearer, and the filter, which can rapidly become wet, is uncomfortable for the wearer.

An object of the invention is to provide an effective respirator, which is uncomplicated and cheap to manufacture, which can be folded to a small size so that it can be carried in ones pocket, which is easily applied so that no leakage arises, and which is comfortable to wear. This has been achieved, according to the invention, in that the wall consists of a foil of flexible material having a perforated central portion, which wall is stretched by the inflated frame into a substanially planar state at a distance from the face, to which wall the filter in the shape of a flexible disc-shaped pad is attached covering the perforated portion of the wall. Due to the fact that the respirator is provided with a flexible inflatable frame it can be kept ready for use in a flat and folded condition which is space saving as well. Before use, the frame is inflated to a low pressure, after which the respirator can be applied to cover the nose or the nose and mouth by means of an elastic band around the back of the neck. Due to the fact that the flexible frame supports the flexible wall of the respirator and not is supported by the usual rigid face mask made, for example, of metal, the frame is sealingly applied against the face notwithstanding substantial irregularities in face contour. The shape of the inflated frame is, moreover, preserved by the wall supported by the frame and provided with the openings for the air passing through the filter. Suitably the ring-shaped frame is, at a portion of its periphery, constricted or interrupted for receiving the ridge of the nose of the wearer, thus facilitating the applying of the frame to the facial contour of the wearer. The wall supported by the frame is suitably used for the attaching of the filter in a simple way by enclosing the filter in an interspace between the wall and a perforated foil of flexible material sealingly joined with the wall along the periphery of the filter. A maximum wall area and, thus, also filter area is obtained whenthe wall supported by the frame is located in the outer plane of the frame, said plane facing away from the face of the wearer. A preferred embodiment of the respirator according to the invention is characterized in that the frame consists of a piece of hose bent and braced in a ring-shaped edge of the wall supported by the frame, which edge is folded back gripping around the hose. Hence, the respirator consists of two separate, easily dismountable parts, viz. on the one hand the wall in the shape of an enclosure having a folded back peripheral edge and the filter attached to said wall, and on the other the hose placed in the folded back edge. This embodiment presents several essential advantages. Above all the folded back edge of the wall constitutes a soft sealing flap contacting the face of the wearer, which flap especially provides a reliable sealing across the ridge of the nose of the wearer even if the hose is ring-shaped and provided with a gap between the ends of the hose for receiving the ridge of the nose. Moreover, such'a respirator is very easy to manufacture, and the hose can easily be removed from the enclosure with the filter, when this filter has become deteriorated or run down, for placing in a fresh enclosure provided with a fresh filter. Further, the wall supported by the hose may have such a length and width that, by turning the wall with respect to the hose, the height of the respirator is changed so, that before turning, the under edge of the respirator is positioned just above the mouth of the wearer, and after turning just beneath the mouth, permitting the use of one and the same respirator for different purposes, even if the hose is provided with an interruption for receiving the ridge of the nose of the wearer.

The invention will be described below with reference to the accompanying drawing, in which: FIG. 1 is a view from behind of an embodiment of the respirator according to the invention, FIG. 2 is a sectional view taken along line 11- in FIG. 1, FIG. 3 is a view from behind of a further embodiment of the respirator according to the invention, FIG. 4 is a sectional view taken along line IV-IV in FIG. 3, FIG. 5 is a sectional view from behind of a modification of the respirator shown in FIGS. 3 and 4, and FIG. 6 is a view similar to FIG. 5 of the respirator after turning of the wall supported by the frame through an angle of 90 with respect to said frame.

The respirator shown in FIGS. 1 and 2 comprises a rectangular plastic foil 1, the central portion of which is provided with a number of holes 2, a ring-shaped plastic foil 3, the outer and inner edge portions of which are sealed by welding to foil 1, a disc-shaped filter 6 covering the holes 2 of the central wall portion of foil 1, and an inner wall 7 consisting of a rectangular plastic foil provided with a number of holes 8 and positioned on the filter 6 and sealed by welding around the periphery of the filter to foil 1. The foil 3 is provided with an opening in which a valve 10 closed by a plug 9 is attached by welding, so that the valve It) can be pulled out for inflating the frame 11 consisting of foils I and 3 and there-after can be pushed in again a distance into the interior of frame 11. At portion 12 the frame is constricted by a curvature of the inner weld seam S of frame 11 for receiving the ridge of the nose of the wearer. Further the outer weld seam 4 of the frame H is designed to form two protruding flaps" 13 provided with holes in which an elastic band 14 is attached intended to extend around the neck of the wearer. The height of the respirator is designed to locate the under edge of the frame 11 just beneath or just above the mouth of the wearer. Alternatively the respirator may have, if the constriction 12 is omitted, such a length and height that one and the same respirator can be used for both these purposes by turning the respirator through an angle of 90. a v

The embodiment shown in FIGS. 3 and 4 comprises two separate parts, viz. an enclosure in the shape of a triangular plastic foil 15 provided with holes 2 and a folded back ring-shaped edge portion 16 in which a frame in the shape of an initially straight hose 17 bent to triangular shape is placed. A filter 6 is attached, as described above, between foil 15 and a triangular inner wall 7 provided with holes 8 and attached by means of a weld seam extending around the periphery of the inner wall to the foil 15. An interspace I8 exists between the ends of the hose 17 for receiving the ridge of the nose of the wearer. Sealing against the ridge of the nose is effected by the foldedback edge portion 16 rectangular shape. The under edge of the respirator is positioned just above the mouth 19 of the wearer. By turning the enclosure through an angle of with respect to the hose 17 the height of the respirator is changed, as illustrated in FIG. 6, so that the under edge of the respirator is positioned just beneath the mouth of the wearer. In this embodiment also the long sides of the respirator are provided with fastening flaps 13 for making it possible to fasten the respirator in this position. The respirator shown in FIGS. 5 and 6 may, of course, have another shape than the rectangular shape, such as, for example, an elliptical shape. Moreover, the hose 17 may be completely closed.

The filter6 may be of different types, known per se, and therefore have not been described in detail. Suitably, however, it consists of an absorption filter, e.g. grains of active charcoal enclosed between sheets of a particle filter, e.g. a fibrous filter. Further, the respirator may be provided with an expiration valve for preventing the filter from being dampened by expiration air.

What I claim is: p

l. A respirator adapted for-inhalation of air from the environment outside of the respirator through a filter therein, said respirator comprising an air-filled inflatable generally ring-shaped tubular frame made of flexible material, a wall supported by saidframe and consisting of a foil made of flexible material having a perforated central-portion, said wall being stretched by said frame in a substantially planar state at a distance from the face of a wearer of the respirator, a flexible filter pad, means for positioning the filter pad in sideby side adjacent relation to the perforated portion of said wall, and means for removably securing said respirator on the face of the wearer thereof.

52. A respirator as claimed in claim 1, wherein said wall includes. an integral edge portion of generally semicircular cross-section turned towards the face of the wearer of the respirator and extending around the periphery of said wall, said tubular frame being titted in said edge portion and secured to said wall by said edge portion.

3. A respirator as claimed in claim 2, wherein said generally ring-shaped frame comprises a hose having two closed ends positioned adjacent each other.

* i i III 

1. A respirator adapted for inhalation of air from the environment outside of the respirator through a filter therein, said respirator comprising an air-filled inflatable generally ring-shaped tubular fraMe made of flexible material, a wall supported by said frame and consisting of a foil made of flexible material having a perforated central portion, said wall being stretched by said frame in a substantially planar state at a distance from the face of a wearer of the respirator, a flexible filter pad, means for positioning the filter pad in side by side adjacent relation to the perforated portion of said wall, and means for removably securing said respirator on the face of the wearer thereof.
 2. A respirator as claimed in claim 1, wherein said wall includes an integral edge portion of generally semicircular cross-section turned towards the face of the wearer of the respirator and extending around the periphery of said wall, said tubular frame being fitted in said edge portion and secured to said wall by said edge portion.
 3. A respirator as claimed in claim 2, wherein said generally ring-shaped frame comprises a hose having two closed ends positioned adjacent each other. 